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Data-Driven Models for Infrastructure Climate-Induced Deterioration PredictionElleathy, Yasser January 2021 (has links)
Infrastructure deterioration has been attributed to insufficient maintenance budgets, lacking restoration strategies, deficient deterioration prediction techniques, and changing climatic conditions. Considering that the latter adds more challenges to the former, there has been a growing demand to develop and implement climate-informed infrastructure asset management strategies. However, quantifying the impact of the spatiotemporally varying climate metrics on infrastructure systems poses a serious challenge due to the associated complexities and relevant modelling uncertainties. As such, in lieu of complex physics-based simulations, the current study proposes a glass box data-driven framework for predicting infrastructure climate induced deterioration rates. The framework harnesses evolutionary computing, and specifically multigene genetic programming, to develop closed-form expressions that link infrastructure characteristics to relevant spatiotemporal climate indices and predict infrastructure deterioration rates. The framework consists of four steps: 1) data collection and preparation; 2) input integration; 3) feature selection; and 4) model development and result interpretation. To numerically demonstrate its utility, the proposed framework was applied to develop deterioration rate expressions of two different classes of concrete and steel bridges in Ontario, Canada. The developed predictive models reproduced the observed deterioration rate of both bridge classes with coefficient of determination (R2) values of 0.912 and 0.924 for the training subsets and 0.817 and 0.909 for the testing subsets of the concrete and steel bridges, respectively. Attributed to its generic nature, the framework can be applied to other infrastructure systems, with available historical deterioration data, to devise relevant effective asset management strategies and infrastructure restoration standards under future climate scenarios. / Thesis / Master of Applied Science (MASc)
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Transfer to higher level of care : a retrospective analysis of patient deterioration, management as well as processes involvedLe Roux, Estelle 06 1900 (has links)
In-patient deterioration is a global phenomena and timely recognition and action improves outcome. Intensive care facilities are scarce and expensive and therefore patient care must be optimal. A retrospective health record analysis was used for this study.
The findings indicated that nursing personnel do not recognize patient deterioration timeuously. However, the implementation of an outreach team and clinical markers training program improved the recognition of patient deterioration in general wards with three hours and 40 minutes.
It is recommended to implement a comprehensive hospital program that addresses the basic knowledge and skills of general ward personnel to observe, recognize, assess and intervene to patients with clinical deterioration. Together with an extensive training program, a basic physiological parameters guideline to activate a team of experts to the bedside, such as an Outreach team, assist nursing personnel to recognize and manage those patients timeuously and ensure treatment in an appropriate level of care. / Health Studies / M. A. (Health studies)
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Influence de la température de cure sur la formation d'ettringite différée dans les bétonsBernard, Alexandre January 2017 (has links)
Une augmentation de la température à jeune âge du béton peut être causée par la chaleur d’hydratation dans le cas d’éléments massifs ou par l’application d’un traitement thermique dans l’industrie de la préfabrication. Lorsque le couple critique température maximale/durée de maintien est dépassé, il y a formation différée de l’ettringite (DEF) expansive pouvant fissurer les pièces.
Les travaux présentés dans ce mémoire ont pour but principal d’établir une limite sécuritaire pour des mélanges V-S pour béton de masse et V-P pour béton préfabriqué régulièrement utilisés par le Ministère des Transports du Québec. Ces bétons utilisent des liants binaires composés de fumée de silice de type GUb-SF et des liants ternaires composés de fumée de silice et de cendres volantes ou de laitier de haut-fourneau. La norme canadienne actuelle (CSA A23.1-14 et CSA A23.4-16) impose une limite fixe de température qui ne dépend ni de la durée de traitement ni du type de liant utilisé.
Le lien, souvent énoncé dans la littérature, entre la réponse d’un liant à un traitement thermique et sa composition chimique et minéralogique, déterminé respectivement par fluorescence X et diffraction des rayons X couplée par la méthode de calcul Rietveld, a pu être confirmé. Le rapport SO3 solubles/Al2O3 est notamment ce qui permet la meilleure estimation de la sensibilité d’un liant.
Le processus de formation différée de l’ettringite est lent et peut prendre plusieurs années. Donc, pour étudier le phénomène, des méthodes d’essais accélérés ont été testées. Des méthodes ont ainsi pu être proposées pour de futurs tests.
Une méthode d’essai rapide d’expansion de barres de mortier permet d’identifier les liants les plus sensibles à la DEF. La formation de la DEF dans les liants les moins sensibles peut être appréciée par le gain de masse de prismes de béton et leur observation microstructurale au microscope électronique à balayage (MEB). Une méthode sur bétons de masse et bétons préfabriqués permet de classer le degré de sensibilité d’un liant face à la DEF selon le gain de masse des prismes de béton. Les liants ternaires montrent une bonne résistance face à la DEF. La sensibilité des liants binaires dépend du rapport SO3 solubles/Al2O3 du liant. / Abstract : A heat cure for concrete can be caused by hydration in massive structures or by thermal treatment in
prefabrication industry. When the limit couple maximum temperature/duration of treatment is exceeded,
the delayed formation of ettringite occurs and leads to cracking in concrete.
The main goal of the work presented in this essay is to establish a safe batch limit for some mixtures, VS
(mass concrete) and V-P (precast concrete) which are often used by MTQ. These concretes use some
cements blended with silica fume and ternary blended cements with silica fume and fly ash or blast
furnace slag. Indeed, the current Canadian standard (CSA A23.1) set a limit which doesn’t depend on
duration of the treatment nor the type of bender.
However, the link between composition of the used bender, with can be determined by X-ray
fluorescence and X-ray diffraction, and the response to a thermal treatment has been confirmed. The
soluble SO3/Al2O3 ratio allows to estimate if a bender is sensitive to heat cure.
The delayed formation of ettringite is a long process which can last a decade. In order to study this
phenomenon, several accelerated test methods have been used. Some of them are available for some
future tests.
An accelerated expansion method using mortar bar allows to spot the DEF-sensitive benders. Delayed
ettringite formation in the less sensitive bender can be estimated by weight gain in concrete prisms and
by observation with scanning electron microscope (SEM). The sensitivity level of a bender can by
estimated using a method based on weight gain. Ternary blended cements show a greater ability to
withstand DEF. The sensibility of binary blended cements depends on soluble SO3/Al2O3 ratio.
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Outils de caractérisation et analyse du comportement des matériaux cimentaires soumis à des cycles de gel-dégel en présence de sels / Tools of characterization and analysis of the behavior of ciment based matérials subjected to freeze-thaw cycles in the presence of saltsBouteille, Sébastien 18 April 2013 (has links)
Un béton exposé à des cycles de gel-dégel peut subir des dégradations généralement identifiées sous deux formes. Le gel interne, d’une part, qui affecte le coeur du matériau et peut aboutir à une microfissuration généralisée de la pâte cimentaire. La sensibilité d’un béton courant à ce mode de détérioration peut être diminuée par la présence d’un réseau de bulles d’air au sein de la pâte cimentaire. L’écaillage, d’autre part, qui est une détérioration de surface. Cette dernière est le plus souvent quantifiée par la perte de masse sur la surface exposée. Cette forme de dégradation est fortement influencée par la présence d’une solution aqueuse proche de la surface de béton exposée et de sa concentration en sels fondants (généralement du chlorure de sodium). Lorsque la formulation d’un béton courant n’est pas adaptée pour résister à ce type d’environnement, les dégradations liées au gel interne et à l’écaillage peuvent pénaliser l’exploitation de l’ouvrage concerné dans des conditions de services attendues. Des essais laboratoire, exposant des corps d’épreuve en béton à des cycles de gel-dégel accélérés, permettent d’évaluer la résistance d’un béton face à ces deux formes de détériorations. La communauté scientifique s’accorde sur les essais permettant de caractériser la détérioration par le gel interne et l’aspect protecteur d’un réseau de bulles d’air. Par contre, l’écaillage est encore abordé par diverses procédures expérimentales qui ne font pas consensus et ont peu évolué depuis le milieu des années 1990 (...) / A concrete submitted to freeze-thaw cycles may undergo damages generally identified under two forms. On one hand, the internal frost affects the whole volume of the concrete. It can resul in generalized microcracks into the ciment paste. The sensibility of a common concrete to this deterioration can be decreased by the presence of a network of air bubbles within the ciment paste. On the other hand, the scaling, is a surface deterioration generaly quantified by the loss of mass from the exposed surface. The scaling is strongly influenced by the presence of a solution and its concentration in salts (generally some sodium chloride), over the exposed concrete surface. When a common concrete is not correctly formulated to resist this environment, its degradation can penalize the exploitation of the concerned structure in expected conditions of services. Laboratory tests exposing bodies of concrete to accelerated freeze-thaws cycles, allow to estimate the concrete resistance when exposed to these two kinds of deteriorations. The scientific community agrees on the internal frost laboratory test and on the protective aspect of a network of air bubbles. But the scaling is still approached by experimental procedures which do not make consensus and have little evolved since the middle of the 1990s (...)
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Testes de envelhecimento acelerado e análise computadorizada de imagens de plântulas para avaliação do desempenho de sementes de soja durante o armazenamento / Accelerated aging tests and automated computer imaging system to assess the performance of soybean seeds during storageYagushi, Juliana Tieme 25 January 2012 (has links)
A avaliação adequada do potencial fisiológico de sementes de soja pode auxiliar as empresas produtoras na tomada de decisões importantes, como a escolha dos lotes a serem armazenados e a definição das condições mais favoráveis à manutenção do nível de desempenho satisfatório das sementes. Neste contexto, o trabalho foi conduzido com objetivo de verificar a eficiência dos testes de envelhecimento acelerado (tradicional e com solução saturada de NaCl) e do SVIS® para avaliar o potencial fisiológico e estimar o potencial de armazenamento de sementes de soja, em comparação com testes recomendados para sementes dessa espécie. Foram utilizadas sementes dos cultivares BRS 184 e M-Soy 7908 RR, cada um representado por seis lotes, armazenados por seis meses em dois ambientes: controlado (20 ºC e 75 % de UR do ar) e de laboratório. O desempenho das sementes foi verificado a cada dois meses durante o armazenamento, por meio de avaliações de germinação, envelhecimento acelerado, condutividade elétrica, tetrazólio, emergência de plântulas em areia e análises SVIS®. Verificou-se que o teste de envelhecimento acelerado (tradicional e com solução saturada de NaCl) e o sistema computadorizado de análise de imagens de plântulas (SVIS®) são eficientes para avaliação do potencial fisiológico de sementes armazenadas de soja. O potencial de armazenamento de sementes de soja é avaliado, com segurança, pela associação dos testes de germinação e de vigor, incluindo o envelhecimento acelerado (tradicional e com solução saturada de NaCl) e as análises SVIS®. / The evaluation of soybean seed vigor has been helping the seed industry in important decisions such as choice of lots to be stored and to defining the appropriate conditions for storability.The objective of this study was to verify the accuracy of accelerated aging tests (traditional and with saturated NaCl) and automated system for seedling evaluation (SVIS®) to assess the physiological potential and estimate the storability of soybean seeds in comparison to the information from accept vigor tests for this species. Two cultivars BRS 184 and M-Soy 7908 RR, each represented by six lots were used. Seeds were stored for six months under two environments: controlled (20ºC and 75% relative air humidity) and normal conditions. Seed performance was evaluated in two month intervals by germination, accelerated aging, electrical conductivity, tetrazolium, SVIS® and sand seedling emergence. Results indicated that accelerated aging (traditional and with saturated NaCl) and automated computer imaging of seedlings (SVIS®) are effective for evaluating the physiological potential of soybean seeds. The storability of soybeans seeds can be consistently evaluated by associating germination and vigor test results, including accelerated aging (traditional and with saturated NaCl) and SVIS®.
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Seismic Behavior Analysis of Concrete Highway Bridges Based on Field Monitoring and Shaking Table Test DataZampieri, Andrea January 2015 (has links)
Concrete highway bridges are important elements of our country's transportation infrastructure; however, only few studies that address their seismic behavior using data collected from instrumented structures are available in the literature. This gap of knowledge impairs full exploitation of structural health monitoring techniques for seismic damage assessment, and improvement of design recommendations. This research is particularly concerned with curved concrete box-girder highway bridges, whose seismic behavior is still widely unexplored due to lack of field monitoring data. By taking advantage of vibration records collected during six earthquake events at the West Street on Ramp, a curved concrete box-girder highway bridge located in Anaheim, California, this research aims at advancing knowledge about the seismic behavior of these bridges. Modal identification of the bridge during the earthquakes is conducted, and sensitivity analysis is carried out to reconcile the observed dynamic characteristics of the bridge with the behavior of its structural elements. Data collected from an instrumented large-scale bridge specimen during shaking table tests are also analyzed to gain insight about the response of the bridge bents during the earthquakes, and propose a strategy to model their seismic behavior. Information from modal identification and the shaking table tests analyses are instrumental in developing a nonlinear finite element model of the bridge, calibrated employing a multistage finite element model updating strategy. In order to evaluate the significance of using the structural-health-monitoring-informed structural model obtained, seismic performance assessment through incremental dynamic analysis is conducted, and results are compared with the predicted performance estimated with a conventional finite element model of the bridge. By advancing knowledge about the seismic behavior of concrete highway bridges, this research may ultimately contribute to improve structural health monitoring practices and design guidelines for this type of structures.
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Capacidade funcional, atividades de vida diária, atividade física, estilo de vida e deterioração cognitiva de pessoas com Síndrome de Down maiores de 20 anos / Functional capacity, Activities of Daily Living, Physical Activity, Lifestyles and Deterioration Cognitive people with higher Down Syndrome 20 Years.Silveira, Jennifer Rodrigues 25 August 2016 (has links)
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Previous issue date: 2016-08-25 / O presente estudo tem como objetivo verificar se existe associação entre a capacidade funcional e os níveis de atividade física, deterioração cognitiva, e atividades de vida diária, em pessoas com Síndrome de Down maiores de 20 anos. A amostra foi composta por 32 indivíduos moradores da zona urbana e
rural da cidade de Pelotas/RS. O estudo prevê a avaliação das capacidades funcionais (CF), das atividades de vida diária (AVD), dos níveis de atividade física (AF), deterioração cognitiva (DC) e questões referentes ao estilo de vida. Para análise estatística foram empregados recursos da estatística descritiva. Para as associações o teste do qui-quadrado e Análise de Variância Univariada (ANOVA). Regressão linear para verificar a variabilidade da CF. Foi adotado um nível de significância de 5% e os dados foram tratados no programa SPSS 22. Fizeram parte do estudo 17 (53%) homens e 15 (46,9%) mulheres, com media de idade de 30,94 anos. Encontrou-se 62,6% (N=20) no nível de obesidade. Foram considerados independentes 37,5% (N=11), parcialmente dependentes 34,4% (N=11) e 28,1% (N=9) classificados como dependentes. Cerca de dois terços da amostra foi classificado com baixa e média CF. Dos estudados 75% (N=24) e 70,8% foram considerados inativos no lazer (questionário) e na AF total (acelerômetro) respectivamente. Em média 12 horas do dia são ocupadas com atividade sedentárias. Verificou-se associação significativa entre ter alta CF para o teste de 800 metros e ser ativo. Encontrouse
78,1% (N=25) dos estudados com maior deterioração cognitiva (DC). A menor DC foi associada a melhores resultados de CF para o teste de sentar e deslocar (p=0,04) habilidades manuais (p=0,02) e levantar-se do solo (p=0,03). Na ANOVA a idade (p=0,04) dos 31-40, ser ativo no lazer (p=0,03) e ser ativo na AF total (p=0,03) foram associadas a melhores resultados do teste de 800 metros. Possuir maiores níveis de AF total (p=0,03), maior independência nas AVDs (p=0,04) e menor DC foram associadas com melhores resultados no teste de sentar e deslocar e maior DC (p=0,03) com resultados inferiores no teste de habilidades manuais. Na regressão linear percebeu-se que as variáveis do G1 (grupo 1) (AF lazer, sexo, idade, DC, doenças associadas, IMC, NSE e AVD total) explicam de forma mais consistente a variabilidade das variáveis de CF. Nota-se um aumento no poder aquisitivo, nos níveis de alfabetização e nas oportunidades de emprego. Foram encontradas poucas associações da AF com AVD e CF. Entende-se com os resultados apresentados que, não é apenas pela condição física associada à SD, mas sim em relação às variáveis de estilo de vida e DC que explicam a variabilidade dos
resultados CF. / The present study aims to verify the existence of associations between functional capacity and physical activity levels, cognitive deterioration, and daily life activities in people older than 20 years with Down syndrome. The sample was made up of 32 individuals from the urban and rural areas of Pelotas/RS.
The study provides an assessment of functional capacity (FC), daily life activities (DLA), levels of physical activity (PA), cognitive deterioration (CD) and issues related to life style. Descriptive statistical resources were used for statistical analysis. Chi-square test and Univariate Analysis of Variance (ANOVA) was used for associations. Linear Regression was used to verify FC variability. A significance level of 5% was adopted and data were treated using the SPSS 22 program. The sample was made up 17 (53%) men and 15 (46,9%) women with an average age of 30.94 years. It was found 62.6% (N=20) at an obesity level, 37,5% (N=11) were considered independent, 34.4% (N=11) partly dependent and 28.1% (N=9) dependent. Around two thirds of the sample was classified at a low and average FC. From the studies, 75% (N=24) and 70.8% were considered inactive at leisure time (questionnaire) and at total PA (accelerometer) respectively. In average, 12 hours a day are used with sedentary activities. A significant association between high FC for the 800meter test and being active was verified. A higher cognitive deterioration was
found in 78.1% (N=25) of the participants. The lower CD was associated to the best FC results for the sitting and dislocation test (p=0.04) manual abilities (p=0.02) and standing up from the floor (p=0.03). In ANOVA, age (p=0.04) of 31-40, being active at leisure time (p=0.03) and active at total PA (p=0.03) were
associated to the best results in the 800-meter test. Having higher levels of total PA (p=0.03), more independence in DLAs (p=0.04) and lower CD were associated to the best results at the sitting and dislocation tests and higher CD(p=0.03) to lower results in the manual ability test. It was noticed, in the
linear regression, that the G1 variables (group 1) (PA at leisure time, sex, age, CD, associated diseases, BMI, NSE and total DLA) explained more consistently the variability of the FC variables. One may notice an increase in buying power, literacy levels and job opportunities. Few associations were found between PA, DLA and FC. The results show that not only physical conditions associated to DS but also variables related to life style and CD explain the variability of the FC results.
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Degradation modeling of concrete submitted to biogenic acid attack / Modélisation de la dégradation du béton due aux attaques acidesbiogéniques.Yuan, Haifeng 03 December 2013 (has links)
La biodétérioration du béton, très courante dans les systèmes d'égouts et de traitement des eaux usées, entraîne une dégradation significative de la structure. Normalement, le processus peut être décrit par les deux étapes suivantes : 1) Des réactions biochimiques produisent des espèces agressives dans les biofilms qui tapissent la surface du béton. L'un des plus importants acides biogéniques que l'on trouve dans les canalisations d'égout est l'acide sulfurique (H2 SO4 ) que est produit par des bactéries sulfo-oxydante (BSO)à partir de l'hydrogène sulfuré (H2 S). 2) Les réactions chimiques entre les espèces agressives biogéniques et les produits d'hydratation du ciment sont responsables de la détérioration du béton. Un modèle de transport réactif est proposé afin de simuler les processus des détériorations chimique et biochimique des matériaux cimentaires en contact avec les BSO et le H2 S ou une solution d'acide sulfurique. L'objectif de ce modèle est de résoudre simultanément le transport et la biochimie / chimie dans les biofilms et les matériaux cimentaires par une approche globale couplée. Afin de fournir un environnement approprié pour la croissance des BSO, la neutralisation de la surface du béton (i.e., l'absorption de H2 S et la corrosion aqueuse de H2 SO4 ) est considérée. Pour obtenir la quantité de H2 SO4 biogénique, la bio-oxydation du H2 S par l'activation des bactéries est simulée par un modèle simplifié. Puis, pour alimenter un environnement convenable pour la croissance des BSO, la réduction abiotique du pH du béton est introduite. Le taux de production de H2 SO4 est régi par la valeur du pH dans les biofilms et la quantité de H2 S dans le gaz. On fait l'hypothèse que tous les processus chimiques sont en équilibre thermodynamique. La dissolution de la portlandite (CH) et du silicate de calcium hydratés (C-S-H), ainsi que la précipitation de gypse (CSH2) et du sulfure de calcium sont décrites par la loi d'action de masse et le seuil des produits d'activité ionique. Pour prendre en compte la décroissante continue du rapport Ca/Si lors de la dissolution de la C-S-H, une généralisation de la loi d'action de masse est appliquée. En simplifiant le processus de précipitation du gypse, un modèle d'endommagement est introduit pour caractériser la détérioration du béton due au gonflement du gypse. Ainsi, l'évolution de la porosité et de la profondeur de la détérioration pendant le processus de dégradation sont pris en compte. Seule la diffusion des espèces aqueuses est considérée. Différents coefficients de diffusion sont utilisés pour divers ions et l'équation de Nernst-Planck est implémentée. L'effet, pendant la détérioration, de la modification de la microstructure sur les propriétés de transport est aussi considéré. Pour les biofilms et les matériaux cimentaires, les équations d'équilibre de masse totale de chaque atome (Ca, Si, S, K, Cl) sont utilisées pour coupler les équations de transport et les réactions (bio) chimiques. Le modèle est implémenté dans un code volumes finis, Bil. Grâce à l'introduction de la méthode des volumes finis, on illustre le couplage du processus bio-chimie dans les biofilms et le processus de la chimiedes matériaux cimentaires. Par ce modèle, certaines expériences rapportées dans la littérature, dont des tests d'immersion chimiques (condition de la solution statique et condition de la solution d'écoulement) et des simulations microbiologiques, sont simulées. Les résultats numériques et les observations expérimentales sont comparés et discutés. L'influence des propriétés des matériaux cimentaires (porosité initiale, couche carbonatée, etc.) et les facteurs d'environnement (concentration de H2 SO4 quantité de H2 S etc) sont aussi étudiés par ce modèle. En outre, une prédiction à long terme est menée / Bio-deterioration of concrete, which is very common in sewer system and waste water treatment plant, results in significant structure degradation. Normally, the process can be described by the two following parts: 1) Biochemistry reactions producing biogenic aggressive species in biofilms which are spread on the surface of concrete. As one of the most significant biogenic acid in sewer pipes, sulfuric acid (H2SO4) is produced by sulfur oxidizing bacteria (SOB). 2) Chemical reactions between biogenic aggressive species and cement hydration products which is responsible for concrete deterioration. A reactive transport model is proposed to simulate the bio-chemical and chemical deterioration processes of cementitious materials in contact with SOB and H2S or sulfuric acid solution. This model aims at solving simultaneously transport and biochemistry/chemistry in biofilms and cementitious materials by a global coupled approach. To provide an appropriate environment for SOB to grow, the surface neutralization of concrete (i.e., the absorption of H2S and aqueous H2S corrosion) is considered. To obtain the amount of biogenic H2SO4, the bio-oxidation of H2S by the activation of bacteria is simulated via a simplified model. To provide a suitable environment for SOB to grow, the abiotic pH reduction of concrete process is introduced. The production rate of H2SO4 is governed by the pH in the biofilms and the content of H2S in gas.It is assumed that all chemical processes are in thermodynamical equilibrium. The dissolution of portlandite (CH) and calcium silicate hydrates (C-S-H) and the precipitation of gypsum (C¯S H2) and calcium sulfide are described by mass action law and threshold of ion activity products. To take into account the continuous decrease of the Ca/Si ratio during the dissolution of C-S-H a generalization of the mass action law is applied. By simplifying the precipitation process of gypsum, a damage model is introduced to characterize the deterioration of concrete due to the swelling of gypsum. Thus, the porosity evolution and deterioration depth during deterioration process are taken into account. Only diffusion of aqueous species are considered. Different diffusion coefficients are employed for various ions and Nernst-Planck equation was implemented. The effect of the microstructure change during deterioration on transport properties is considered as well. For both biofilms and cementitious materials, the balance equations of total mass of each atom (Ca, Si, S, K, Cl) are used to couple transport equations and (bio-)chemical reactions. The model is implemented within a finite-volume code, Bil. Following the introduction of principle of the finite volume method, the coupling of the bio-chemistry process in biofilms and chemistry process in cementitious materials is illustrated. By this model, some experiments reported in literature, including chemical immersion tests (statical solution condition and flow solution condition) and microbiological simulation tests, are simulated. The numerical results and the experimental observations are compared and discussed. The influence of properties of cementitious materials (initial porosity, carbonated layer, etc.) and environmental factors (concentration of H2SO4, content of H2S, etc.) are investigated by this model as well. Furthermore, a long term predictionis conducted
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Degrada??o natural de toras e sua influ?ncia nas propriedades f?sicas e mec?nicas da madeira de cinco esp?cies florestais / Natural degradation of toras and your influence in the properties of the wood five forest speciesTrevisan, Henrique 22 February 2006 (has links)
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Previous issue date: 2006-02-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The first part of this work was led from August from 2004 to August 2005. The objective of
evaluating the influence of two enviroments: forest and open field, in the durability of recently
abated toras of five forest species: Eucalyptus urophylla " Eucalyptus " (Myrtaceae), Melia
azedarach L. " Cinamomo " (Meliaceae), Lophantera lactescens Ducke, Lanterneira
(Malpighiaceae), Pinus elliottii "Pinus" (Pinaceae), Inga marginata " Inga " (Mimosaceae), as
well as to evaluate the beetles and termites occurrence in the respective wood and enviroments,
through collections of wood sub-samples, in defione time, and of collections of the ocurrente
termites, in the dismantle of the experiment. The beetles occurrence were just registered in the
timber of Inga marginata and in the field from inside the forest, and the identified species were:
Euplatypus parallelus and Teloplatypus ratzeburgi, both of the family Platypodidae. 56,6% of the
timber were enrolled with the presence of termites in the field from inside thee forest, where the
species found were: Nasutitermes minor, Nasutitermes jaraguae and Heterotermes longiceps. In
the open field, it was registered 20% of the timber with the presence of termites, with a since
species found, Heterotermes longiceps. For the evaluation of the natural durability, a
classification system was adopted, where through the deterioration level, notes were attributed.
The smallest indexes, for both enviroment were registered by the timber of E. urophylla, 60
inside the forest and 70 of outside forest. The second part of this work had the objective of
evaluating the influence of the intemperism, in the physical and mechanical wood properties.
Mechanical rehearsals were accomplished with the wood non degradation, for further comparison
with the values obtained from the rehearsals accomplished in the wood coming from the
intemperized timber. Significant reductions of the density were observed only the exposed wood
from the rotten field of the forest. The wood of L. lactescnes was the only one that didn't show
the resistance from the compression and the module of elasticity and rupture, in the static flex,
altered after the intemperism, in the two enviroments. The largest reductions in the module of
elasticity and rupture, as well as in the resistance from compression, were registered in the wood
of E. urophylla, in both enviroments. The third part of this work had the objective of studing the
natural resistance of the wood, Coptotermes gestroi action, as well as to trace a discussion on the
methodologies that evaluate the resistance of the wood to termites and to propose a protocol that
contemplates the referred study, in a more appropriate way, and that can predict, in a more real
way, the resistance of the wood when in service. The wood that losis more mass, front the action
of C. gestroi was the L, lactescens and the one that loses less mass was M azedarach. E.
urophylla and L. lactescens were framed in the resistant class and M. azedarach and I.
marginata, as highly resistant to C. gestroi in the rehearsal of free choice. The suggested method,
denominated semicampo , was efficient for the evaluation of natural resistance of the wood
and feeding preference. / A primeira parte deste trabalho foi conduzida entre agosto de 2004 a agosto de 2005, e teve como
objetivo avaliar a influ?ncia de dois ambientes, florestal e campo aberto, na durabilidade de toras
rec?m abatidas de cinco esp?cies florestais: Eucalyptus urophylla Eucalipto (Myrtaceae),
Melia azedarach L. Cinamomo (Meliaceae), Lophantera lactescens Ducke, Lanterneira
(Malpighiaceae), Pinus elliottii Pinus (Pinaceae), Inga marginata Inga (Mimosaceae), bem
como avaliar a ocorr?ncia de coleobrocas e t?rmitas nas respectivas madeiras e ambientes,
atrav?s de coletas de sub-amostras de madeira, em tempo determinado, e de coletas dos t?rmitas
ocorrentes, na desmontagem do experimento. Foi registrada a ocorr?ncia de coleobrocas apenas
nas toras de Inga marginata e no campo de dentro da mata, sendo as esp?cies identificadas:
Euplatypus parallelus e Teloplatypus ratzeburgi, ambas da fam?lia Platypodidae. Registrou-se
56,6 % das toras com a presen?a de t?rmitas no campo de dentro da mata, sendo que as esp?cies
ocorrentes foram: Nasutitermes minor, Nasutitermes jaraguae e Heterotermes longiceps. No
campo a c?u aberto, foi registrado 20% das toras com a presen?a de t?rmitas, de uma ?nica
esp?cie ocorrente, Heterotermes longiceps. Para a avalia??o da durabilidade natural, adotou-se
um sistema de classifica??o. Os menores ?ndices de comportamento, o que denotam madeiras
mais degradadas, para ambos os ambientes, foram registrados nas toras de Eucalipto, sendo 60
para dentro da mata e 70 para fora da mata. A segunda parte deste trabalho teve como objetivo
avaliar a influ?ncia do intemperismo em propriedades f?sicas e mec?nicas da madeira. Ensaios
mec?nicos foram realizados com a madeira n?o intemperizada, para posterior compara??o com os
valores obtidos dos ensaios realizados nas madeiras procedentes das toras intemperizadas.
Redu??es significativas da densidade foram observadas apenas nas madeiras expostas no campo
de apodrecimento de dentro da mata. A madeira de L. lactescens foi a ?nica que n?o teve a
resist?ncia a compress?o e o m?dulo de elasticidade e ruptura, na flex?o est?tica, alterados ap?s o
intemperismo, nos dois ambientes. As maiores redu??es no m?dulo de elasticidade e ruptura,
bem como na resist?ncia a compress?o, foram registradas na madeira de E. urophylla, nos dois
ambientes. A terceira parte deste trabalho teve como objetivo estudar a resist?ncia natural das
madeiras, a a??o de Coptotermes Gestroi, bem como tra?ar uma discuss?o sobre as metodologias
que avaliam a resist?ncia da madeira a t?rmitas e propor um protocolo que contemple o referido
estudo, de forma mais adequada, e que possa predizer, de forma mais real, a resist?ncia da
madeira quando em servi?o. A madeira que mais perdeu massa, frente ? a??o de C. gestroi foi a
de L.lactecens e a que menos perdeu foi a de M. azedarach. A madeira de E. urophilla e L.
lactescens foram enquadradas na classe resistente e M. azedarach e I. marginata, como
altamente resistente a Coptotermes gestroi no ensaio de livre escolha. O m?todo sugerido,
denominado semicampo, demonstrou-se eficiente para avalia??o da resist?ncia natural das
madeiras e prefer?ncia alimentar.
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Estratégias de controle da deterioração aeróbia em silagem de milho e seu valor alimentício para vacas em lactação / Strategies to control top losses in corn silage and the nutritive value responses in Holstein cowsAmaral, Rafael Camargo do 03 October 2011 (has links)
Foram realizados três experimentos visando avaliar diferentes estratégias de vedação. No experimento I, objetivou-se avaliar as características fermentativas e a estabilidade aeróbia das silagens de milho vedadas com diferentes tipos de filme plástico, aplicação na camada superior de aditivo químico ou microbiano e proteção do filme com terra, visando o controle da deterioração aeróbia. Houve diferença para o tipo de filme plástico utilizado, onde foi observado maiores valores de temperatura para as silagens vedadas com o filme de polietileno. As silagens aditivadas com benzoato de sódio ou Lactobacillus buchneri apresentaram menores perdas de matéria seca e menores valores de pH com relação a silagem não aditivada. Apenas em três amostras foram detectadas a presença de aflatoxina B1. No experimento II, objetivou-se avaliar estratégias de vedação, com base na proteção do filme plástico, visando o controle da deterioração aeróbia nas zonas periféricas do silo e o comportamento dessas silagens durante o período de aerobiose. No momento da abertura dos silos a contagem de leveduras foi maior para a silagem que não teve proteção sobre o filme plástico. A digestibilidade verdadeira in vitro da matéria seca apresentou diferença, sendo que as silagens que receberam proteção sobre a lona apresentaram os maiores valores em relação a silagem sem proteção sobre o filme plástico. No experimento III, objetivou-se avaliar diferentes tipos de filmes plásticos na vedação de silos horizontais e suas interferências relativas a qualidade das silagens, ao desempenho de vacas em lactação e qualidade do leite produzido. As maiores quantidades de silagem descartada foram para os tratamentos com a lona preta e lona dupla face. As maiores taxas de permeabilidade da lona ao oxigênio foram observadas para os filmes dupla face e preto de material virgem. A dieta que continha silagem proveniente do silo vedado com lona preta de material reciclado com proteção de bagaço apresentou o maior valor para a produção de leite, sendo a menor média verificada para o tratamento que continha filme plástico preto de material virgem. Ao longo das semanas de experimentação foi verificada a presença de aflatoxina B1 em todas as silagens. A partir do mês de agosto foi verificada positividade para aflatoxina M1 entre as amostras de leite. A dieta que continha silagem proveniente do silo vedado com lona preta de material reciclado e proteção de bagaço apresentou o maior valor de digestibilidade, tanto da matéria seca como da matéria orgânica das dietas. O polímero de poliamida, a proteção da lona com terra ou bagaço e o uso de aditivos como Lactobacillus buchneri ou benzoato de sódio reduzem a deterioração aeróbia de silagens de milho. A proteção da silagem contra o aquecimento, pelo uso da poliamida ou da proteção com bagaço, auxilia na obtenção de silagem de melhor qualidade e facilita o manejo pela redução da mão-de-obra no descarte de silagem deteriorada. O desempenho animal é afetado pela estratégia de vedação utilizada, podendo até mesmo afetar qualidade higiênica do leite produzido. / Three experiments were conducted to evaluate different strategies to cover the silo. The experiment I evaluate the fermentation profile and aerobic stability of com silage covered with different types of plastic sheets, applying additives in the top layer and, protecting the fi 1m with soil, to reduce the top losses in com silages. Higher temperature values were observed for the com silage covered with the polyethylene film. The use of additives showed lower DM losses and pH values in relation the control silage. The presence of aflatoxin 81 was detected in three samples only for the silage covered with polyethylene film, without additive and without soillayer over the top of the film. The experiment 11 was designed to study the effectiveness of covering methods to reduce the top losses in maize silages. The. yeast count was higher for control silage. The dry matter digestibility showed higher values for the protected silos in relation to unprotected treatment. The experiment 111 was designed to evaluate different plastic sheets to seal horizontal silos and their influence on the silage quality, Holstein dairy cows performance and milk quality. There was no difference between treatments for the fermentation profile. The silages temperature values in the silo top and top side increased in relation to samples in the panel center. The deteriorated discarded silage showed high values in silages covered with black virgin polyethylene and black-on-with polyethylene films. Those plastics films showed the highest rates of oxygen permeability. The diet containing silage from black recycled polyethylene with bagasse protection showed the highest value for milk yield, while the lowest milk yield was found to the black virgin polyethylene treatment. Over the experimentation period, the presence of aflatoxin 81 in silage was observed. The diet containing silage from black recycled film protect with bagasse treatment showed the highest digestibility of both dry matter and organic matter. The polyamide plastic film, the use of soil or sugarcane bagasse as a plastic film protection and, application of additives on the silo upper layer, reduce the com silage aerobic deterioration. Inhibiting the silage warming by using polyamide plastic film or sugarcane bagasse, helps in obtaining better quality silage management, reducing the costs and labor associated with the discarded silage. Animal performance is affected by the strategy used to seal the silage and may even affect hygienic quality of milk
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